There was a time when people did not know what type of atmosphere venus had. There are some things that can immediately be observed about it. First of all, it has a lot of meteor craters. One can only guess how many meteors have landed here. There are also some constant lava flows.
There are also some areas that are smoother than the rest because of the lava. The core of Venus is known to be made out of iron while its mantle is also rocky similar to how the mantle of the earth is. The earth and venus have a lot of differences especially when it comes to the planets’ ability to sustain life.